Safety valve for tanks



March 19, 1935. 3 w. N 1,994,770

SAFETY VALVE FOR TANKS Filed May 13, 1951 Patented Mar. 19, 1935 U ITED STATES SAFETY vALvE, FOR TANKS George W. King, Cofifeyville, Kans, assignor of" two -twelfth's to Lce T. Englnnd, two-tweliths to John E. Malian, both offlofieyville, Kans,

and seven-twelfths to Roy: T." Osborn, New

York, N.

" Application as 1 2, 1931,. Serial 1510. 537,054

My invention relates to'safety valves for tanks and pertains more particularly to a structure of this type which embodies several operating advantages over those now in common use. .1 One object of my invention is to devise a safety valve which is constructed and arrangedto inhibit an accumulation of ice, snow, frost, dirt, cinders and foreign matter in general that might otherwise affect the free movement of the valve, and which isalsodesigned to prevent the entrance of water through the valve into the tank.

A further object is to provide a valve of the character indicated which istotally free oi any pocketor trap formations and which substan- 1; tially, presents a smooth, deflecting exterior to matter that might clog the valve. V A further object is to devise a safety valve which cannotbe opened with an ordinary wrench from the outside of the valvaand which is readily interchangeable withvalves of the present type, For the purpose of illustration-my improved valve will be described in connection with a tank car, although it will be understood that the device is susceptible of wider adaptation to tanks inge'neral and regardless of size, condition, place or character of use. Y Inthe railway transportation of volatile, inflammable vapors and-liquids, it is required that the .tank'car be-providedwithsometype of a 3 safetyvalve which will operate to relieve the insure rises abovea predetermined setting of the valve. The present type of valve comprises a cuplike formation surrounding the valve opening which has a tendency to become clogged with dirt and cinders, or to accumulate snow and frost formations, or waterwhich might eventually become frozen and affect the movement of the valve. Occasionally, such valves will not open at the pressure for which they are set because of such accumulations, or they may be maintainedin an open position owing to the lodging of interfering matter on the valve seat, so that rain may be driven into the contents within the tank. The cup around the valve also provides a fire hazard in that it provides a receptacle for holding inflammable liquids. Another objection to the present standard type of valve is that it may be readily removed by a simple wrench in the hands of an unauthorized person, resulting in the loss of a part of the contents of the car by theft. The present invention is designed to provide a valve which positively overcomes the foregoing disadvantages as will presently appear.

These and further objects of ,my invention will ternalpressure within the .tank when this pres- Claims;- (01. lei-53 be setforth in the following specification, refer-- ence being, had to the accompanying drawing, and the novel means, by which said objects are effectuated will be definitely pointed out in the claims. p

In the drawing: i V ure 1 is an elevation showing, the dome portion of a railway tank car with my improved valve 1 structure, lookingin the direction of the arrow 3 in Fig. 2. v M v v,

Referring to the drawing, the numeral des-, ignates a portion of a tank which is provided with the usual dome 11 having a filler cap ,12. The top offthe dome 11 has formed therein an opening 13 which is encircled by a flange 14 riveted to the dome 11. The flange le has anannular, upstanding wall which is internally. threaded as at 15 to receive the valve structure as will now be described. l A cylindrical valve casing 16 is threaded in, the flange 14 and is provided at its upper end with a frusto-conical valve seat 17. Beneath the valve Seat 1'7, the casing 16 is provided withan in with the seat 1'7 by means of a helical spring 22 whose upper end abuts against the shoulder 18 and whose lower end against a follower 23 which slides freely within the casing 16. In order to maintain the follower in abutting position to the spring 22, a stud 24 passes freely through the follower 23 and its upper end is threaded as at 25 in the valve 19, a lock nut 26 serving to maintain the threaded engagement of the stud 24 with said valve. Beneath the follower 23, an adjusting nut 27 and a lock nut 28 are threaded on the stud 24, whereby any desired tension may be set up in the spring 22 in order to establish the pressure at which the valve 19 will rise and relieve the internal pressure within the tank.

My improved safety valve operatesin precisely the same manner as do the safety valves now in parts operate to deflect any particles, whether of:

a liquid or of a solid nature, away fromthe valve structure. When the valve 19 is closed, as shown in Fig. 2, the abutting faces of said valve and the casing 16 are separated by an extremely narrow, annular opening 29 whosewidth is insufficient to permit the passage therethrough of particles having a size that would interfere with the normal operation of the valve, as well as preventingthe accumulation and building up of snow,zfrost'and ice formations within the opening. V I

As an additional advantage, it may be noted that, externally of the valve, there are not'any parts which may be convenientlyengaged by a wrench for the purpose of removing the valve structure and permitting unauthorizedtampering with the contents of the 'tank 10. The valve is therefore largely theft-proof, aswell as leakproof against the passage of liquids either into or out of the tank. The curved nature of the valve face 20 insures the proper seating of the valve 19 at all times, regardless of any misalignment of parts arising by reason of irregularities in fit-or Wear.

While I have shown one set-ofelements and combinations thereof for eifectuating my improved safety valve, it will be understood that the same is intended for purpose of illustration only and in no wise to restrict my device to the exact forms and structures shown, for many changes may be made therein without departing from the spirit of my invention.

I claim: 7 7

1. A safety valve for a tank comprising in combination, a casing having an internal shoulder extending 'therearound, the upper surfaceiof said shoulder forming a valve seat and the under surface a spring seat, a valve having a face for cooperating with said seat and extending substantially to the edge of said casing, .the lateral sur- This relation r faces of the casing and valvebeing smooth and.

valve exterior free from pocket formations, the

portions of said casing and valve outwardly from;v

said seat, andface being slightly spaced from each other in the closed position of the valve, a shouldered extension on the valve projecting into the casing beyond the internal shoulder, and a spring encircling the extension between the shoulder thereof and the spring seat for yieldingly 'ma.in-

taining the valve in closed position.

bination, a casing having an internal shoulder extending therearound, the upper surface of said shoulder being formed as a frusto-conical valve seat and the under surface a spring seat, a valve having a convex face for cooperating with said seat and extending substantially to the outer edge of said casing, the lateral surfaces of the casing and valve being smoothand rounded and the top 2. A safety valve for a tank comprising in com-- surface of the valve'beingsmooth and domeshaped to thereby provide a valve exterior free spring seat for yieldingly maintaining thepva lve in closed position. 7

3. Asafety valve for a tank-comprisingin com bination, a casing having an internal shoulder extending therearound, the upp er surfaceo f said" shoulder forming a valve seat and theunder' sure face a springseat, a valve having a face'fo'r cooperating with said seat and extending substan-" tially to the outer edge of said casing, the lateral surfaces of the casing and valve being smooth androundedand the top surface of the valve being smooth and dome-shaped-to thereby provide a valve exterior free from pocket formations, the

portions of said casing andvalve outwardly from said seat and face being slightly spaced from each other in the closed position of, thevalvaa stem mounted at its upper end insaid valve and having a follower plate at its lower end, and'a' spring encircling saidstem between said plate and spring seat for yieldingly maintaining-said valve in closed position. GEORGE W. KING. 

